after some advise for my 455 pontiac .has anyone used these pistons they are 0cc to increase compression.also what are some options for thin head gaskets without having to o ring i really appreciate all the help im getting
cheers blake

Also, the -060 is for a 0.060" oversize piston (Summit's catalog listing makes it look like that p/n is for a standard piston). -030 would be a 0.030" over, etc. So be sure to order the right oversize for your engine. The machinist will need to assess the condition of your block to give you his oversize recommendation.

Then you have to order the pistons and give them to the machinist for him to measure before doing the final hone. The type of ring used (plain, moly, etc.) needs to be known as well so the hone finish is correct for the rings being used.